THE IMMUNE SYSTEM
Definition: The immune system can be defined as: the body system that fights off infection and pathogens. It is not the first line of defense, your skin and other physical barriers are. When pathogens get past these barriers, your immune system fights the infection.
White Blood Cells
White blood cells include a number of different types of cells.
The white blood cells exterminate the pathogens that have passed the physical barriers. When a pathogen enters the body, basophils in the blood stream release chemical signals which attracts other white blood cells to the site of the infection. There are now two different occurrences that can take place: 1) If the pathogen is a parasite, eosinophils come and spray the parasite with poison 2) If the pathogen is a virus, bacterium, or fungus, neutrophils and macrophages come to “take care” of it. Neutrophils and macrophages are phagocytes, which is a cell that destroys pathogens by surrounding and engulfing them. Then lymphocytes come to the site of the infection, and there are two types
There are several parts that make up the immune and lymphatic system. You can learn more about the anatomy of them on the anatomy page. Below we will describe their functions and how they fight off infection.
T-lymphocytes and B-lymphocytes (T and B cells) T cells destroy body cells with the infected pathogen while B cells produce proteins that inactivate pathogens who have yet to find a host cell.
There are 3 proteins used by the Immune system
1) Complement Proteins: made by white blood cells, and do a number of things including: weakening the membrane of a pathogen which allows water to center and burst, attract phagocytes to infected area, and cause pathogens to stick to blood vessels making them easy to find.
2) Antibodies: proteins made by B cells, and destroy pathogens. They are like the “missiles” of the body. They are sent to the pathogens in order to destroy them. They destroy pathogens by, activating complement proteins, binding to the membrane, or clumping the pathogens together which allows phagocytes to engulf them.
3) Interferons: These proteins are produced by infected body cells, and they cause other body cells to produce enzymes which protect them from pathogen intrusion.
Passive and Active Immunity
Passive Immunity: Occurs when the body does not need the Immune Response; Includes Genetic and Inherited Immunity.
Active Transport: Does include Immune Response and your body responds to the intrusion of a pathogen.
*NOTE: Continue reading to learn what the Immune Respnses.
White Blood Cells
White blood cells include a number of different types of cells.
The white blood cells exterminate the pathogens that have passed the physical barriers. When a pathogen enters the body, basophils in the blood stream release chemical signals which attracts other white blood cells to the site of the infection. There are now two different occurrences that can take place: 1) If the pathogen is a parasite, eosinophils come and spray the parasite with poison 2) If the pathogen is a virus, bacterium, or fungus, neutrophils and macrophages come to “take care” of it. Neutrophils and macrophages are phagocytes, which is a cell that destroys pathogens by surrounding and engulfing them. Then lymphocytes come to the site of the infection, and there are two types
There are several parts that make up the immune and lymphatic system. You can learn more about the anatomy of them on the anatomy page. Below we will describe their functions and how they fight off infection.
T-lymphocytes and B-lymphocytes (T and B cells) T cells destroy body cells with the infected pathogen while B cells produce proteins that inactivate pathogens who have yet to find a host cell.
There are 3 proteins used by the Immune system
1) Complement Proteins: made by white blood cells, and do a number of things including: weakening the membrane of a pathogen which allows water to center and burst, attract phagocytes to infected area, and cause pathogens to stick to blood vessels making them easy to find.
2) Antibodies: proteins made by B cells, and destroy pathogens. They are like the “missiles” of the body. They are sent to the pathogens in order to destroy them. They destroy pathogens by, activating complement proteins, binding to the membrane, or clumping the pathogens together which allows phagocytes to engulf them.
3) Interferons: These proteins are produced by infected body cells, and they cause other body cells to produce enzymes which protect them from pathogen intrusion.
Passive and Active Immunity
Passive Immunity: Occurs when the body does not need the Immune Response; Includes Genetic and Inherited Immunity.
Active Transport: Does include Immune Response and your body responds to the intrusion of a pathogen.
*NOTE: Continue reading to learn what the Immune Respnses.
Immune Responses
Your body has several different responses to foreign pathogenic invasion.
Here are some examples of non-specific Immune Responses.
1) Inflammation: This includes the swelling, redness, and itchiness of a pathogenic infected region. For example: when you get a cut. This response starts when basophils release histamines (which are chemicals) that cause the body cells to spread/expand. This allows white blood cells to move out of the capillaries and into the site of infection. When the white blood cells successfully destroy the infection histamines are no longer produced, the white bloods cells leave, and the swelling goes down.
2) Fever: A fever occurs when macrophages release chemical that tell the brain to increase the body’s temperature. Temperatures around 100 degrees Fahrenheit increase the production of interferons and speed up the maturation rate of white blood cells which allow more cells to fight the infection. When a temperature reaches 103 degrees Fahrenheit it becomes very dangerous because your brain loses control of your temperature. This can lead to death.
Here is information about specific immune responses you need to know:
1) For a specific immune response to work correctly, the body hast to be able to tell the difference between healthy and infected cells. This is where the antigens come into play. They have different proteins on the surface which allows the white blood cells to determine whether the cell is a “friend or foe”.
2) Specific immune responses produce acquired immunity. Acquired immunity occurs when you white blood cell fight of an infection, and memory cells are created. And these memory cells remember an antigen on a pathogen which allows your body to fight of that pathogen quicker.
3) There are two types of specific responses:
a. Cellular Immune Response: Involves the T cells. Phagocytes realize there is a pathogenic invasion, and engulf the pathogen and then reveal the pathogens antigens. The T cell encounters this phagocyte, and binds to it. Proteins are then released to activate the T cell. The T cell then begins to divide into two different T cells: activated and memory. Activated T cells will bind to and destroy infected body cells, while the memory T cells will be kept as a “reserve” for future invasions.
b. Humoral Immune Response: Involves antibodies. When a pathogen binds to a B cell, the B cell engulfs the pathogen and puts the antigen on its surface. When a T cell finds this B cell, it binds to the antigens. And the T cell releases chemicals that activate the B cell. The activated b cells divide into B cells and memory B cells. These activated B cells can produce 2000 antibodies per second. The antibodies then destroy the pathogen in the ways you have already learned.
What is Tissue Rejection?
Tissue rejection occurs when your white blood cells detectforeign antigens on a donated tissue. This is very dangerous and can lead to death.
This is what tissue rejection looks like:
Here are some examples of non-specific Immune Responses.
1) Inflammation: This includes the swelling, redness, and itchiness of a pathogenic infected region. For example: when you get a cut. This response starts when basophils release histamines (which are chemicals) that cause the body cells to spread/expand. This allows white blood cells to move out of the capillaries and into the site of infection. When the white blood cells successfully destroy the infection histamines are no longer produced, the white bloods cells leave, and the swelling goes down.
2) Fever: A fever occurs when macrophages release chemical that tell the brain to increase the body’s temperature. Temperatures around 100 degrees Fahrenheit increase the production of interferons and speed up the maturation rate of white blood cells which allow more cells to fight the infection. When a temperature reaches 103 degrees Fahrenheit it becomes very dangerous because your brain loses control of your temperature. This can lead to death.
Here is information about specific immune responses you need to know:
1) For a specific immune response to work correctly, the body hast to be able to tell the difference between healthy and infected cells. This is where the antigens come into play. They have different proteins on the surface which allows the white blood cells to determine whether the cell is a “friend or foe”.
2) Specific immune responses produce acquired immunity. Acquired immunity occurs when you white blood cell fight of an infection, and memory cells are created. And these memory cells remember an antigen on a pathogen which allows your body to fight of that pathogen quicker.
3) There are two types of specific responses:
a. Cellular Immune Response: Involves the T cells. Phagocytes realize there is a pathogenic invasion, and engulf the pathogen and then reveal the pathogens antigens. The T cell encounters this phagocyte, and binds to it. Proteins are then released to activate the T cell. The T cell then begins to divide into two different T cells: activated and memory. Activated T cells will bind to and destroy infected body cells, while the memory T cells will be kept as a “reserve” for future invasions.
b. Humoral Immune Response: Involves antibodies. When a pathogen binds to a B cell, the B cell engulfs the pathogen and puts the antigen on its surface. When a T cell finds this B cell, it binds to the antigens. And the T cell releases chemicals that activate the B cell. The activated b cells divide into B cells and memory B cells. These activated B cells can produce 2000 antibodies per second. The antibodies then destroy the pathogen in the ways you have already learned.
What is Tissue Rejection?
Tissue rejection occurs when your white blood cells detectforeign antigens on a donated tissue. This is very dangerous and can lead to death.
This is what tissue rejection looks like:
The Immune System and Technology
Technology and the Immune System work together in the following ways
1) Antiseptics: are chemicals that kill pathogens outside the body.
2) Antibiotics: Target and kill one type of bacterium.
3) Antibiotic resistance: Occurs when bacteria mutate and are no longer killed by antibiotics.
4) Vaccine: A small dosage of a pathogen injected into the blood stream in order to help the immune system build resistance, and memory cells.
1) Antiseptics: are chemicals that kill pathogens outside the body.
2) Antibiotics: Target and kill one type of bacterium.
3) Antibiotic resistance: Occurs when bacteria mutate and are no longer killed by antibiotics.
4) Vaccine: A small dosage of a pathogen injected into the blood stream in order to help the immune system build resistance, and memory cells.
Overreactions
Sometimes your immune system can overreact. Here is some vocab you need to know:
1) Allergy: An oversensitive reaction to a certain antigen.
2) Allergen: Antigens that cause an allergic reaction.
3) Anaphylaxis: Occurs when the immune system releases a large amount of histamine, which causes airways to tighten and cause tissues to no receive sufficient oxygen.
4) Autoimmune Disease: Occurs when white blood cells attack the body’s healthy cells. Her are some examples:
a. Rheumatoid arthritis: break down joint tissues
b. Type 1 diabetes: attacks the pancreas, which stops sugar digestion
c. Hashimoto’s thyroiditis: attacks thyroid gland causing a decrease in hormone production
d. Multiple sclerosis (aka MS): breaks down the myelin sheaths which disrupts nerve communication
e. Graves’ disease: stimulates thyroid gland resulting in excess hormones
Remember histamines? Well this is released when the white blood cells encounter a pathogen, but in an allergic reaction histamines are unnecessary released. For example, if you are allergic to peanuts and you eat apeanut your throat swells. This is because your white blood cells think the peanut is a pathogen and release histamines to begin the immune response, which causes the inflammation of the throat.
1) Allergy: An oversensitive reaction to a certain antigen.
2) Allergen: Antigens that cause an allergic reaction.
3) Anaphylaxis: Occurs when the immune system releases a large amount of histamine, which causes airways to tighten and cause tissues to no receive sufficient oxygen.
4) Autoimmune Disease: Occurs when white blood cells attack the body’s healthy cells. Her are some examples:
a. Rheumatoid arthritis: break down joint tissues
b. Type 1 diabetes: attacks the pancreas, which stops sugar digestion
c. Hashimoto’s thyroiditis: attacks thyroid gland causing a decrease in hormone production
d. Multiple sclerosis (aka MS): breaks down the myelin sheaths which disrupts nerve communication
e. Graves’ disease: stimulates thyroid gland resulting in excess hormones
Remember histamines? Well this is released when the white blood cells encounter a pathogen, but in an allergic reaction histamines are unnecessary released. For example, if you are allergic to peanuts and you eat apeanut your throat swells. This is because your white blood cells think the peanut is a pathogen and release histamines to begin the immune response, which causes the inflammation of the throat.
THE LYMPATIC SYSTEM
FUNCTION OF LYMPHATIC SYSTEM
This system filtrates the body by producing white blood cells in the bones (long bones) and disease-fighting antibodies. The lymphatic syste collects fluids that leak from blood circulation, cleanse it, then return it to the circulatorysystem (the heart).
The Lymphatic System includes:
1) Lymph: Fluid, and white blood cells, that flow throughout the lymphatic capillaries, and arteries.
2) Lymph Nodes: This is where lymph collects.
3) Lymphocyte: White blood cell that plays an important role in the fighting off of pathogens. (Remember T and B cells)
Click here to watch a cool animation of how the Immune and Lymphatic systems work!
1) Lymph: Fluid, and white blood cells, that flow throughout the lymphatic capillaries, and arteries.
2) Lymph Nodes: This is where lymph collects.
3) Lymphocyte: White blood cell that plays an important role in the fighting off of pathogens. (Remember T and B cells)
Click here to watch a cool animation of how the Immune and Lymphatic systems work!